颞叶癫痫大鼠海马区NR2B／PSD-95的动态表达变化

目的:观察N-甲基-D-天冬氨酸受体2亚基B(NR2B)和突触后致密物95(PSD-95)蛋白在锂-匹罗卡品致大鼠海马表达的动态变化,探讨其在颞叶癫癎发生、发展中的作用。方法:采用锂-匹罗卡品颞叶癫癎大鼠模型,用免疫组织化学法观察不同时间点大鼠海马CA1、CA3、DG区NR2B和PSD-95蛋白表达。结果:NR2B和PSD-95蛋白在大鼠海马分布广泛,表达丰富;大鼠腹腔注射锂-匹罗卡品后,NR2B和PSD-95蛋白在海马各区表达逐渐减少,24h降至低谷,与对照组比较差异有显著意义(P<0.01);此后逐渐回升,但仍低于对照组;30d在海马CA1、CA3区表达再次降低,与对照组比较有显著意义(P<0.05)。结论:NR2B和PSD-95蛋白表达下调可能分别参与颞叶癫癎急性期和慢性自发发作期的保护性机制。

Altered Expression of NR2B/PSD-95 Protein in the Hippocampus of Temporal Lobe Epilepsy Rats

Aim: To observe the expression of N-methyl-D-aspartic acid receptor 2B (NR2B) andpostsynaptic density 95 (PSD-95) proteins in hippocampus of Li-pilocarpine-induced epileptic rat.Methods: Rats were injected Li-pilocarpine intrapentoneally to establish a temporal lobe epilepsy model.At 2 h, 6 h, 24 h, 3 d, 15 d, 30 d, 60 d after lithium-pilocarpine (Li-PILO) induced seizures, theexpression of NR2B and PSD-95 proteins in the CA1,CA3,dentate gyrus of hippocampus wereanalyzed by using immunohistochemistry. Results: NR2B and PSD-95 protein were expressed abundantlyin all regions of hippocampus. Li-PILO induced seizure causes a significant decrease of NR2B andPSD-95 protein at 24 h and 30 d in the CA1 and CA3 of hippocampus, accompanying a decrease onlyat 24 h in the dentate gyrus. Conclusion: The down-regulation of NR2B/PSD-95 protein expressionmight participate in the neuronal protection during acute stage and chronic phase of temporal lobeepilepsy.